The grounding of the Sea Empress in February 1996 caused one of the largest and
most environmentally damaging oil spills in European history. About 72,000 tonnes of crude
oil were released into the seas around the coast of South-West
Wales, a region renowned for the beauty and diversity of its coastline.

The Pembrokeshire coastline boasts National Park status and numerous other conservation designations. It has also been one of the best
studied coastlines in North-West Europe, providing an unusually good baseline of
information against which to gauge oil spill impacts. Scientists from various
organizations participated in a major monitoring programme to study the effects of the
spill on the coastal environment and wildlife. An independent group, the Sea Empress
Environmental Evaluation Committee (SEEEC), was set up by the government to evaluate the
results of more than 100 scientific studies. SEEEC organized a scientific
conference on the environmental impacts of the oil spill (February 1998, Cardiff, Wales),
during which the final SEEEC report was launched. The conference
proceedings were also published in 1998.
A number of other scientific reports and papers describing the impacts of the oil spill have also
been published, and more are in preparation.

The pollution was at its height during late February and
early March of 1996 at which time huge slicks were at sea, and many shores were
experiencing large-scale bulk oil pollution. By April, as a result of natural dispersion
and the clean-up operation, little bulk oil remained at sea and many shores had regained a
semblance of normality. Wave-exposed rocky shores improved quickly through natural
cleansing, followed by the intensively-cleaned sands of the main bathing beaches, most of
which were reopened for Easter. However, many shores
were affected by residual oil pollution through the summer of 1996. Contamination
persisted out of sight within shingle, sands and muds and within surviving wildlife.
Autumnal storms remobilized buried oil, causing the temporary reappearance of sheens and
tar balls on many beaches. This storm action accelerated the natural cleansing of the
coast. By spring of 1997, few shores showed visible evidence of oiling.

As for wildlife impacts, birds at sea were hit hard
during the early weeks of the spill, resulting in thousands of casualties. In contrast,
the grey seal population appeared little affected and
impacts to subtidal wildlife were limited. However, much damage was caused to shorelines affected by bulk oil. Shore seaweeds and
invertebrates were killed in large quantities. Mass strandings of cockles and other shellfish occurred on sandy beaches. Rock pool fish were also
affected. However, a range of tough shore species were seen to survive exposure to bulk
oil and lingering residues.

On many shores the process of wildlife recovery began soon after the bulk oil dispersed
naturally or was removed. Surviving wildlife was supplemented by plant and animal
recolonizers. Recovery is likely to be protracted in the case of sheltered shores that
continue to harbour deep-seated lingering residues of oil (e.g., some muddy shores in
Milford Haven).

As a result of the incident, fishing activity was banned.
However, following intensive Government testing of shellfish and finfish, the ban
was lifted in stages.

The visual aesthetic appeal of most shores used for recreation was largely restored by
the summer of 1996, by which time bathers, surfers and SCUBA divers returned to many
localities along the coast of South-West Wales.